U.S. Pat. No. 6,698,194 discloses a two-stroke engine having an exhaust-gas muffler wherein a resonance pipe closed at one end is mounted between the outlet from the engine and the inlet into the exhaust-gas muffler. The resonance pipe is configured as a separate component which can be mounted in the attenuating space of the muffler so as to be wound in a spiral configuration. A resonance pipe of this kind is complex to manufacture.